20. In December of 1987 an automobile manufacturer pleaded no contest to criminal charges of odometer tampering and agreed to pay more than $16 million in civil damages for cars that were test-driven with their odometers disconnected. (A) cars that were test-driven with their odometers disconnected (B) cars that it had test-driven with their disconnected odometers (C) its cars having been test-driven with disconnected odometers (D) having test-driven cars with their odometers disconnected (E) having cars that were test-driven with disconnected odometers 这个题完全不懂啊,正确选项D是什么意思什么结构啊?